Looking to shed a few pounds? There's an app for that. Dozens, in fact.

While many of these apps have cool tech features that are good at tracking calories and exercise, a new study reveals they do little to help people overcome common pitfalls like having too little time to exercise or relapsing into bad eating habits.

Experts reviewed 30 of the most downloaded free and paid weight-loss apps for iPhone and Android. They compared the apps' features to 20 proven weight-loss strategies used in the Diabetes Prevention Program run by the Centers for Disease Control and Prevention. The program teaches physical activity and healthy eating in a yearlong group setting and has helped participants lose 5 to 7 percent of their body weight.

The study results, published in the American Journal of Preventative Medicine, showed almost all of the apps focused on users setting goals for the number of pounds they want to lose, and calories they want to consume or burn. The apps then helped track progress, often generating charts and graphs. Goal setting and progress tracking are a few of the CDC's tested weight-loss techniques.

But only a handful of the apps offer other successful strategies, like teaching portion control, substituting unhealthy food with nutritious alternatives, and suggesting ways to work exercise into existing daily routines. None of the apps included stress or time management techniques or tips on understanding nutrition labels and combatting relapses.

While researchers are excited about the possibilities technology can bring to the battle against obesity, they call on app makers to look beyond diet, activity and weight tracking as they develop the next generation of health and fitness apps.

Here are a look at weight loss apps by the numbers:

2

Apps that researchers gave high marks to because they include 13 out of 20 CDC-proven weight-loss strategies, the most of any app. The apps are MyNetDiary, a free iPhone app, and its $3.99 counterpart, MyNetDiary PRO.

28

Apps the researchers studied that include five or fewer of the CDC's 20 proven weight-loss strategies.

14

Apps that cost money of the 30 studied, ranging from 99 cents to $4.99. Researchers found that paid apps are no more likely than free apps to include the CDC's proven weight-loss strategies.

17

Apps that include a barcode scanner that calls up food's nutritional information. It was the most popular tech enhancement, and it's a feature not available in traditional weight loss programs. Fourteen apps have a social networking component that connects people with other app users. Six have the capability to send users e-mail reminders when their tracking lapses.